CNC hot wire cutter from scanners

[Raul] built a CNC hot wire cutter that he uses for cutting shapes out of foam. His device uses two flat bed scanners to provide two planes of motion. One scanner arm has the foam mounted on it and provides the Y-axis movement. The other scanner has the hot wire mounted on it and provides the X-axis movement. The cutting wire is mounted on a flexed bow made from heavy gauge coat hanger wire.

He tapped into the logic board of one scanner to gain access to the motor movements. The other is connected through a couple of H-bridges. Both are controlled by an Atmel AVR ATmega128 which in turn takes its commands from a connection with a computer printer port. A python program uses vector graphic files in SVG format and traces the outline for cutting.

We’ve got a video of this in action after the break. At our request, [Raul] took some time to post a set of pictures and make comments on them. Thanks for the hard work and great job!

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29 thoughts on “CNC hot wire cutter from scanners”

yet another useless hack. I suppose if you need a thin piece of foam less than 7 x 7 cut out this will be perfect for you, but my bet is the creators never use it other than exhibiting how “31337” their hacking skills are.

This is an awesome hack… I’ve been looking for something just like this to create custom attache case cut outs, it’d also be incredibly handy for modifying the foam inserts on automotive interiors.. something I have to do often by hand and could do with perfect precision using something like this.

@kirov
Whoa man, whats all the angst for? Just because you don’t see the usefulness of something doesn’t mean its not useful. You could use these to cast metal and make models, or home made gears for drive trains.

And even if it is useless, who cares? Its a fun looking weekend project.

Probably one of the most ignorant comments I’ve seen on hackaday. Raul set out to automate something and did a fine job. Maybe you don’t need foam cutouts, I bet you don’t need an NES guitar or a VR maze either but that doesn’t make them useless.

This would be great for making model airplane wings in cross section pieces, or just the ribs. I wonder if it would go through thin ABS plastic sheets as well. At any rate, for small modeling and rapid prototyping this is a pretty neat hack.

Lost foam casting… that foam can now be turned into aluminum bronze or even iron. Think lost wax investment casting… except foam = wax and sand (or other material) = investment. Instead of melting the wax from the mold, the metal tends to be poured right into the low density foam surrounded by the mold material. (This is not intended to be an all inclusive explanation of the subject…)

This is a really nice build. I have been plotting against a few old scanners, myself, but I haven’t gotten far on that project. This guy’s work could really help me, to build my own project (@ Kirov). So, even though this only slices foam, it’s well built, well-documented, uses parts others have available, and it works.

You know that this is a really great hack for people interested in the lost foam casting method. CNC rapid protoyping for any type of aluminum part. just glue on your risers, nest the parts together and pour in your molten aluminum. Blam! rough cast intricate parts. better than most people can do by hand.. and quicker too.

The speed on that rig is as impressive as much as anything. I could see myself using this to make ink stamps for my mum as she’s been on a handicrafts tip for a few months now.
Wonder how much further it could be taken to get a hobby scale band saw under control, maybe as a material controller with the saw stationary. Then a whole pile of new materials come in to play.

I don’t think you realize how much a cnc foam cutter cost, of course this one is smaller, so its only a couple of hundred, but if you’ve ever played warhammer or other table top you know how annoying cutting foam can be. This would be perfect to cut in layers and then come through with a hand cutter and make it into an actual hill or barrier